Eva Forsbom: Text-specific thesauri for information access
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"You take what you have, said Cajsa Warg"

For many subtasks in an information system, a thesaurus can be a
useful resource. The thesaurus can help tasks such as indexing,
searching, browsing, linking, topic segmentation and
summarisation. The usefulness, however, is dependent on the amount and
kind of information present in the thesaurus. But what if we don't
have a good-coverage, high-quality thesaurus? And what kind of
information is useful?

In the seminar, I will present a system for building dynamic
text-specific thesauri. The thesauri are dynamic in that they are created
during analysis from a number of linguistic knowledge bases, and
text-specific because only meanings signalled by the text are
activated.

I present preliminary results for some combinations of Swedish
resources. The thesauri are evaluated in a series of information
access subtasks involving various summarisation strategies.